Thermoelectric Transport in Graphyne Nanotubes
Thermoelectric Transport in Graphyne Nanotubes
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DOI：
10.1021/jp406536e
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发表时间：
2013-09
影响因子：
3.7
通讯作者：
Xiao-ming Wang;Shu-shen Lu
中科院分区：
文献类型：
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作者：
Xiao-ming Wang;Shu-shen Lu
在密度泛函紧束缚（DFTB）框架下，采用非平衡绿色函数（NEGF）方法研究了石墨炔纳米管（GNT）的热电输运性质.我们发现，随着管径的增加，带隙和热电优值ZT都呈现阻尼振荡。随着化学势绝对值的增加，可以观察到Seebeck系数的符号变化，这归因于GNT中的迷你带的形成。此外，热电性能由于氢化而降低。出乎意料的是，其中一个氢化的GNT的声子热导保持，这是由于表面粗糙度和应变弛豫的抵消。我们的调查和研究结果是非常重要的，广泛的兴趣，扩大石墨烯社区。
The thermoelectric transport properties of graphyne nanotubes (GNTs) are investigated by using the nonequilibrium Green’s function (NEGF) method, as implemented in the density functional based tight-binding (DFTB) framework. We find that both the band gap and thermoelectric figure of merit ZT show a damped oscillation with the tube diameter increased. Sign changes can be observed for the Seebeck coefficient, as the absolute value of the chemical potential increased, which is attributed to the minibands formation in the GNTs. In addition, the thermoelectric performance is reduced due to hydrogenation. Unexpectedly, the phonon thermal conductance of one of the hydrogenated GNTs is maintained, which is due to the counteraction of the surface roughness and the strain relaxation. Our investigations and findings are very important and of broad interest for expanding the graphyne community.